Solid-state image pickup device and method for manufacturing the same

Abstract

In a solid-state image pickup device, a thickness of an insulating film, a width and a thickness of wirings, a length of the wirings, or a diameter of bump portions formed on the wirings is formed so that a capacitance of a capacitor structure generated between a solid-state image sensor chip, and the wirings and the bump portions is not more than a desired value. Thereby, sensitivity of the solid-state image pickup device is not lowered at high-frequency driving.

1 . A solid-state image pickup device comprising:
 a semiconductor substrate;   solid-state image sensors formed on an upper surface of the semiconductor substrate;   through wirings penetrating the semiconductor substrate; and   wirings formed on a lower surface of the semiconductor substrate and connected to the through wirings, wherein   a thickness of an insulating film insulating the wirings from the semiconductor substrate, a width and a thickness of the wirings, a length of the wirings, or a diameter of bump portions formed on the wirings is formed so that a capacitance between the semiconductor substrate and the wiring is not more than a desired value.   
   
   
       2 . The solid-state image pickup device according to  claim 1 , wherein
 the value of the capacitance is not more than 2 pF.   
   
   
       3 . The solid-state image pickup device according to  claim 1 , wherein
 the thickness of the insulating film is not less than 2 μm and not more than 10 μm.   
   
   
       4 . The solid-state image pickup device according to  claim 1 , wherein
 the width of the wiring is not more than 200 μm and not less than 10 μm.   
   
   
       5 . The solid-state image pickup device according to  claim 1 , wherein
 the diameter of the bump portions is not more than 200 μm and not less than 50 μm.   
   
   
       6 . A method for manufacturing a solid-state image pickup device comprising:
 forming solid-state image sensors on an upper surface of a semiconductor substrate; and   forming through wirings connecting wirings formed on a lower surface of the semiconductor substrate to the solid-state image sensors, on the semiconductor substrate, wherein   a thickness of an insulating film insulating the wirings from the semiconductor substrate, a width and a thickness of the wirings, a length of the wirings, or a diameter of bump portions formed on the wirings is formed so that a capacitance between the semiconductor substrate and the wiring is not more than a desired value.   
   
   
       7 . The method for manufacturing a solid-state image pickup device according to  claim 6 , wherein
 the value of the capacitance is not more than 2 pF.   
   
   
       8 . The method for manufacturing a solid-state image pickup device according to  claim 6 , wherein
 the thickness of the insulating film is not less than 2 μm and not more than 10 μm.   
   
   
       9 . The method for manufacturing a solid-state image pickup device according to  claim 6 , wherein
 the width of the wiring is not more than 200 μm and not less than 10 μm.   
   
   
       10 . The method for manufacturing a solid-state image pickup device according to  claim 6 , wherein
 the diameter of the bump portions is not more than 200 μm and not less than 50 μm.